Synthetic oil used to be something only performance cars ... The alphanumeric codes on a quart of oil—5W-30, 0W-20, etc.—denote its “weight,” or viscosity. Thicker, higher-viscosity ...

you should be using a full synthetic or synthetic blend 5W-20 oil. A 6.2-liter HEMI engine requires 0W-20 oil, which is a bit lighter when the engine is cold. Drivers of vehicles with 6.4-liter ...